Crucible



Nov. 30 a 1926.

J. D. M. SMITH CRUCIBLE Filed Juhe 8' 1926 liil lill@ Patented Nov. 30, 1926.

Par-enr rr-ics.l

unirse srnrssy LAY/'ID MAN SMITH, OIF EDGBSTUN, E'GIIAiKTD, ASSCGNOR TO VJ. 95 J. LIIvILTE-D- OF BRSXNGCHAM. ENGLAND. i

CARUCIBLE.

Application 'Filed June 8.71926, Serial Elo. 1.14:,424Qai1d in Great Britain June 5', 1525.

vThis invention has reference to improvements in or relating' to Cruciblesremployedin chemical an` ysis. v

Writh crucibles for this purpose now grenorally in use in which crucibles the lid rests are unreliable or the determination rendered.

abortive by reason ot the loss ot contents ot the Crucible due to such causes as the decrepitation ot solid matter, the creeping of liquids between the Crucible and the undersurtace ot the lid, by the fracture ot the lid, or again by the sudden lifting or dislodgment ol the lid due to the violent liberation of gases or vapours whereby loss of contents may ensue by spurting or otherwise. Loss may also occur in these determinations where it is required to add further reagents to the Contents of the Crucible since in order to effect these additions it is necessary to remove the Crucible lid thereby exposing the determination to risk of error by reason ot loss ot contents -from one Cause or another.

The present invention has tor its object the provision of an improved Crucible for use in chemical analysis whereby the altorementioned sources oi' error are eliminated to a great extent and the determinations etiected with greater accuracy than heretofore and with a minimum ot attention.

The invention consists of an improved Crucible 'for use in chemical analysis wherein the Crucible body is provided with a lid adapted to be located within the body so that the peripheral edge of the said lid is disposed below the rim ot the Crucible body, said lid being provided with a flange within which are 'formed a plurality ot serrations or apertures.

The invention will now be described with particular reference to the accompanying sheet ot drawings, wherein Figure l is a part sectional front. elevation of a Crucible constructed in accordance with the invention.

Figure 2 is a section on the plane indicated by the line 2-2 Figure l looking in the direction ot the arrow in the said iigure.

Figure B is a tront elevation ot the crucible lid, and

Figure 4 is a plan of Figure 3.

The Crucible body 5 which may be made of fused silica or other suitable material is of the ordinary shape and is of a size larger than that ofthe Crucible of normal pattern that would ordinarily be employed tor the operation contem lated.` Y The Crucible is Closed by means o a lid 6 which fits within Vthe Crucible bo-dy so that the upper surface within the body the lower edge ot the iange t 6b contacts with the inner periphery of the Crucible body and supports the lid the portion of the flange above the said edge being separated from the walls ot the Crucible by an annular space which is in Communication with the interior ot the Crucible body by means of the serrations or apertures 6 in the iiange 6b as is clearly indicated in Figure l.

It will be appreciated thatwith a Crucible constructed in accordance with this invention the disadvantages resulting from the employment ot the ordinary Crucible provided kwith a lid adapted to rest and overhang the Crucible body, are largely eliminated. For example, according to the present invention loss of contents due to decrepitation or spurting is prevented since the sole means of egress of the contents from the Crucible body is by way ot the serratons in the -flange ot the Crucible lid and by reason of the juxtaposition of the Outer periphery of said rim to the inner periphery ot the Crucible body such of the contents of the Crucible as may escape throunjh the serrations in the flange are merely discharged on to the walls of the Crucible body and are not lost. Or again. in the Case of the creeping ot a liquid the liquid merely passes, at the placesy of Contact of Crucible and lid, from Crucible to lid, owing to the temperature gradient between heated Crucible and cooler lid. Further, if it be desired to add any reagents such addition may be made without removing the lid whereby loss oit the contents due to any possible violent chemical action is avoided. Moreover, in the event of breakage of the lid from any cause no loss Will result since the residual contents will still remain Within the crucible body.

By reason of the advantages accruing from a Crucible constructed in accordance With the invention due to the elimination of the sources of error referred to the duration of the determinations can be considerably reduced since the degree of care and attention is less than that required in determinations With crucibles of known construction.

I Wish it to be understood that I do not limit the invention to crucibles of fused silica as it is equally applicable to crucibles made from other materials, for example, porcelain, fire-clay, nickel, or other metal, and further, if it be desired to employ crucibles of the standard size the reduction in the effective capacity due to the location of the lid Within the body of the Crucible may be compensated for by forming the lid of a dome shape.

Claims:

l. A Crucible for use in chemical analysis comprising a crucible body, a lid adapted to be located Within the body so that the peripheral edge of the said lid is disposed beloW the rim of the crucible body, and a plurality of serrations or apertures in the said lid.

2. A Crucible for use in chemical analysis comprising` a Crucible body, a lid adapted to be located Within the body so that the peripheral edge of the said lid is disposed beloW the rim of the Crucible body, a flange on said lid and a plurality of serrations or apertures formed in the said flange.

In testimony whereof, I have signed my name to this specification.

JOHN DAVID MAIN SMITH. 

